Читать книгу Bovine Reproduction - Группа авторов - Страница 139

A subjective evaluation of concentration should be made by examining the tube containing the semen to ensure that a representative sample has been obtained. A poorly concentrated sample will be watery and translucent containing <250 million sperm per milliliter, whereas a concentrated sample, typical of a mature bull, will appear creamy and grainy when examined against a dark background containing at least one billion sperm per milliliter. Very concentrated, high‐volume ejaculates occur in cases of sperm accumulation. A watery, poorly concentrated sample from a mature bull is typical in cases of testicular degeneration. Closely linked to volume, the concentration of a semen sample also varies with the collection technique. EEJ is not an appropriate method of determining the sperm‐producing capability of a bull.